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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 13 |
| 3 | 37 |
| 4 | 97 |
| 5 | 407 |
| 6 | 1397 |
| 7 | 4531 |
| 8 | 16029 |
| 9 | 55471 |
| 10 | 188735 |
| 11 | 651517 |
| 12 | 2246015 |
| 13 | 7712899 |
| 14 | 26544813 |
| 15 | 91374201 |
| 16 | 314289321 |
| 17 | 1081352347 |
| 18 | 3720918175 |
| 19 | 12801778315 |
| 20 | 44045879629 |
| 21 | 151549077973 |
| 22 | 521423489151 |
| 23 | 1794025850189 |
| 24 | 6172623965117 |
[1,13,37,97,407,1397,4531,16029,55471,188735, 651517,2246015,7712899,26544813,91374201, 314289321,1081352347,3720918175,12801778315, 44045879629,151549077973,521423489151, 1794025850189,6172623965117] |